What was the effect of the 15th amendment?
a. it legalized the separate but equal doctrine.
b. it gave black men the right to vote.
c. it struck down the jim crow laws in the south.
d. it made former slaves citizens of the united states.

THE ANSWER IS 
b. it gave black men the right to vote

Currently, as of february 2016, an american traveling in france would be by the exchange rate. the weakness of the euro and the strength of the us dollar means that items in france cost less to an american than they otherwise would. of course, if this trend reverses and the us dollar weakens and the euro strengthens, such as was happening in early 2008, an american traveling in france would have an adverse experience because items would cost relatively more.